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KSR Number: KSRA53001

Interventions to improve the uptake of cervical cancer screening among lower socioeconomic groups: a systematic review

Risk of Bias Assessment

Overall summary: Risk of bias unclear

Bottom Line

Current evidence suggests that HPV self-testing or the use of lay health advisors to educate women about cervical cancer and Pap smear testing may improve the uptake of cervical cancer screening among lower socioeconomic groups. However, it was unclear in the review how many reviewers were involved in quality assessment, meaning reviewer error and bias cannot be ruled out. Further high quality studies are needed to further support these findings.

Risk of Bias Assessment

Overall summary Risk of bias unclear

Unclear

No information was provided regarding the number of authors involved in the risk of bias assessment, meaning reviewer error and bias cannot be ruled out.

A. Did the interpretation of findings address all of the concerns identified in Domains 1 to 4? No information
B. Was the relevance of identified studies to the review's research question appropriately considered? Probably yes
C. Did the reviewers avoid emphasizing results on the basis of their statistical significance? Probably yes
Risk of bias in the review Unclear

Details of Review

Number of studies 16
Number of participants 54350
Last search date June 2016
Review type Intervention
Objective To assess the effectiveness of interventions to improve the uptake of cervical cancer screening specifically among lower socioeconomic groups.
Population Women eligible to participate in a cervical cancer screening program who were of lower socioeconomic groups, based on race, ethnicity, income and/or geographical area.

Studies conducted in upper/ middle income countries were excluded if the intervention targeted a population deemed to be of a higher socioeconomic status.
Interventions Strategies to enhance attendance within an organised program; local interventions targeted at lower socioeconomic groups (in-reach strategies (e.g. interventions directed at healthcare providers or patients belonging to a healthcare provider), outreach strategies (mailed information and/or telephone calls), interventions led by lay health advisors, mixed strategies); HPV self-testing; or a combination of these.
Comparator Another intervention or a non-exposed control group.
Outcome Primary outcome: Rate of uptake or non-uptake of cervical screening.

Secondary outcomes: Sustainability and cost effectiveness.
Study design Randomised controlled trials (RCTs) or quasi RCTs.

Reviews and qualitative studies were excluded.

Results

In terms of human papillomavirus (HPV) self testing interventions, two studies reported an improvement in attendance or uptake of cervical screening when HPV self-testing kits were provided (either by post or by a nurse visiting women at home) to lower socioeconomic groups when compared to the control group (smear invitations) (1 study, n=18,730 non-attending French women; 1 study, n=25,061 Mexican women).

In terms of lay health advisors (LHAs) interventions, two studies reported an improvement in cervical cancer screening rates when LHA delivered cervical cancer education sessions when compared to other educational programs such as diabetes (one study; n=487 Latina/Hispanic women in USA) and general health (one study; n=102 Korean women in USA). One study reported an improvement in cervical cancer screening uptake for women who had received Pap tests twice already but not for women who had never been screened following education on cervical cancer and Pap testing through the use of audiovisual materials compared to the direct mailing of educational materials promoting and encouraging physical activity (one study, n=234 Vietnamese American women). Two studies reported no difference in Pap screening rates following 12-week small group education about general cancer compared to an educational program about community skills (1 study, n=512 Latina women in USA); or following an individual or social support group setting (1 study, n=1006 Latina women in USA). Four studies delivering an LHA-led education package based on theoretical models of behavioural change reported an improvement in cervical cancer screening uptake (1 study, n=381 Hispanic women in USA); 1 study, n=398 Samoan women; 1 study, n=613 Mexican women in USA; 1 study, n=373 Vietnamese women in USA).

In terms of outreach interventions, one out of two studies reported an improvement in cervical screening uptake after sending a simple fixed appointment letter compared to no intervention (45% uptake vs. 26%; 1 study, n=320 inner city women in Thailand); and one out of two studies reported no difference in cervical screening uptake for telephone counselling (including assistance with booking appointments) compared to a two-sentence telephone call encouraging women to visit their local health professional (1 study, n=1316 low and moderate income populations in USA).

In terms of in-reach interventions, one study reported no difference in cervical screening uptake for home visits with an educational leaflet and factsheet compared to no intervention (1 study, n=304 inner-city community women in Thailand).

In terms of mixed interventions, one study reported no difference in screening rates for outreach interventions using LHAs to facilitate access to screening compared to outreach interventions consisting of education and computer reminders (1 study, n=3215 low income, multi-ethnic women in USA).

Full Risk of Bias Assessment

The research objectives and inclusion criteria were clearly stated. No restrictions were imposed based on the study characteristics or sources of information.

1.1 Did the review adhere to pre-defined objectives and eligibility criteria? Probably yes
1.2 Were the eligibility criteria appropriate for the review question? Probably yes
1.3 Were eligibility criteria unambiguous? Probably yes
1.4 Were all restrictions in eligibility criteria based on study characteristics appropriate (e.g. date, sample size, study quality, outcomes measured)? Probably yes
1.5 Were any restrictions in eligibility criteria based on sources of information appropriate (e.g. publication status or format, language, availability of data)? Probably yes
Concerns regarding specification of study eligibility criteria Low

MEDLINE, CINAHL, EMBASE and the CENTRAL databases were searched for relevant studies. The Grey literature was searched using the OpenGrey database and hand searches of citations was conducted to locate all potentially relevant reviews and research papers. The reported Embase strategy appeared to be adequate, however it was unclear how well it worked in Medline. The strategy was translated inconsistently across the other databases searched. The searches were restricted to studies published between January 2006 and June 2016 and this was found to be appropriate. Two reviewers were independently involved in the study selection process and any disagreements were resolved by consulting a third author.

2.1 Did the search include an appropriate range of databases/electronic sources for published and unpublished reports? Probably yes
2.2 Were methods additional to database searching used to identify relevant reports? Probably yes
2.3 Were the terms and structure of the search strategy likely to retrieve as many eligible studies as possible? Probably yes
2.4 Were restrictions based on date, publication format, or language appropriate? Probably yes
2.5 Were efforts made to minimise error in selection of studies? Yes
Concerns regarding methods used to identify and/or select studies Low

Two reviewers were independently involved in the data extraction process. Sufficient study characteristics appear to have been extracted to allow for the interpretation of the results. Relevant study results appear to have been extracted. Methodological quality of the included studies was assessed using the Cochrane risk of bias assessment tool for RCTs. No information was provided regarding the number of authors involved in the risk of bias assessment.

3.1 Were efforts made to minimise error in data collection? Yes
3.2 Were sufficient study characteristics considered for both review authors and readers to be able to interpret the results? Probably yes
3.3 Were all relevant study results collected for use in the synthesis? Probably yes
3.4 Was risk of bias (or methodological quality) formally assessed using appropriate criteria? Probably yes
3.5 Were efforts made to minimise error in risk of bias assessment? No information
Concerns regarding methods used to collect data and appraise studies Unclear

The synthesis appeared to include all of the eligible studies. A narrative synthesis was performed to summarise the findings due to the heterogeneity among the populations, interventions and contexts. The quality of individual studies was considered in the synthesis.

4.1 Did the synthesis include all studies that it should? Probably yes
4.2 Were all pre-defined analyses reported or departures explained? Probably yes
4.3 Was the synthesis appropriate given the degree of similarity in the research questions, study designs and outcomes across included studies? Probably yes
4.4 Was between-study variation minimal or addressed in the synthesis? Probably yes
4.5 Were the findings robust, e.g. as demonstrated through funnel plot or sensitivity analyses? Probably yes
4.6 Were biases in primary studies minimal or addressed in the synthesis? Probably yes
Concerns regarding synthesis and findings Low

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